Exhibition exhibit
Hygienic Seal Demonstrator
for hygienic seals from Freudenberg
Exhibition stand for the drinktec trade fair in Munich
When hygiene convinces visually.
The exhibition exhibit makes it visible at a glance how particles accumulate in dead spaces of a standard seal, while the hygienic seal from Freudenberg remains completely residue-free. In the acrylic cylinder filled with water it becomes apparent how important the right seal design for hygiene and process safety is.
Operating principle of the exhibition exhibit
A hydro screw, whose motor is built into the base, stirs up fluorescent granulate in the water. The granulate, which glows under UV light, settles on the protruding standard seal as it sinks, while the hygienic seal remains residue-free.
Virtual 3D model
Already in the concept phase the exhibit was fully designed in 3D, to optimize proportions, function and design early on.
Real exhibition exhibit
From the digital design a precisely manufactured exhibition model made of acrylic glass, stainless steel and black lacquered wood was created in the real world.
Exhibition exhibit in action
In action the exhibit unfolds its full effect. Flowing granulate and lighting effects create a dynamism that immediately attracts attention.
Uncompromising design - high-quality and pure
Blue shimmering water and orange glowing granulate reflect Freudenberg's corporate design. A deep black base, high-gloss polished stainless steel screws and clear acrylic glass emphasize purity and precision. The black light provides a modern, almost futuristic look and reinforces the impression of innovation and high quality.
Eyecatcher - fascination in the water flow
Already from afar the demonstrator draws the attention of trade fair visitors. Glowing clouds of granulate whirl in the water. A dynamic spectacle that immediately arouses curiosity. Technically exciting and visually impressive, the demonstrator is the eye-catcher on the trade show booth.
Focus - the decisive difference
At first glance the hygienic seal hardly differs from a standard seal. Once installed, however, it becomes visible how big the difference for hygiene actually is. Standard seals create dead spaces where residues accumulate and hygienic risks arise. The hygienic seal from Freudenberg relies on precise geometries and smooth surfaces that allow thorough cleaning and significantly reduce the risk of contamination.
In the following image the standard seal on which the fluorescent acrylic granulate settles can be seen below in the exhibit. The hygienic seal above, however, remains residue-free.
The transparent flanges of the exhibit deliberately direct the view to the seals. The protrusion of the standard seal and the flush fit of the hygienic seal are clearly visible from all perspectives. The domed acrylic glass acts like a magnifying glass and enlarges the residues on the standard seal. This makes the advantage of the hygienic variant clearly recognisable.
In the exhibit the protrusion of the standard seal was deliberately made slightly more pronounced so that the microscopic problem can be staged with coarse granulate.
Standard seal
The protrusion creates dead spaces
Hygienic seal
The precise geometry prevents dead spaces
Noble stainless steel screws high-gloss polished and certified
The high quality standards of Freudenberg were to be reflected in the exhibition appearance down to the last screw. Therefore, EHEDG certified fastenings made of polished stainless steel from the company Kipp were installed. A set of screws M12 consisting of a screw, a nut and a washer with seal costs around 50 euros net.
The above image shows a considerable total value of around 3,000 euros net and the following image the noble result from polished stainless steel in combination with acrylic glass.
Development and design of the exhibition exhibit
Before production the exhibit was fully constructed digitally. This allowed function, design and proportions to be precisely coordinated and made the designs visually accessible to Freudenberg's Hygienic Seal team. The result was a reliable basis for an exhibit that could be implemented on time and successfully.
Drive unit with Freudenberg lip seal (Simmerring)
The water screw is positioned inside the cylinder and is driven by a brushless electric motor in the base of the model. For sealing the shaft feedthrough two Simmerrings from Freudenberg arranged in sequence are used as radial shaft seals. Between them runs a full ceramic ball bearing that guides the shaft precisely. The entire feedthrough is visible from the outside through the transparent acrylic glass bottom and is mirrored by the aluminum plate underneath.
Brushless electric motor for the hydro screw
The water screw of the exhibit is driven by a maintenance-free outer rotor motor that already develops a high torque at low speeds and achieves peak performance of up to 540 watts. The motor is mechanically decoupled via elastic rubber spacer bolts, effectively reducing vibrations and structure-borne noise. An additional propeller supports the cooling of the drive unit.
Impressive lighting effects with black light using RGBAW+UV LEDs
Six RGBAW+UV LEDs with a total output of 72 watts enable flexible lighting effects and render not only red, green and blue but also amber, white and UV with high color fidelity. The black light makes the fluorescent granulate impressively glow. The unit is housed in a black painted, 3D-printed enclosure with CNC-milled aluminum fascia. The power is supplied via two threaded rods, while a third transmits the DMX signal for precise control.
Microelectronics and control of the exhibition exhibit
The drive and LED unit of the exhibit are controlled by an ESP32 microcontroller running at 240 MHz. The software is developed in C++ and coordinates motor movements and light effects. The sequence starts automatically at an adjustable interval or manually via a pushbutton in the base. First, the granulate is agitated by a short reverse run and then distributed throughout the cylinder with a quick forward run. After settling, a slow reverse run clears the mirror at the bottom and makes the oil seal visible.
power electronics and power supply
A high-quality brushless ESC from the model hobby sector is used as the power electronics. It converts the 12 volt DC from the power supply into a frequency-controlled three-phase current for the motor. The LED unit is operated at 24 volts, which is generated via a boost converter. An additional voltage regulator provides 5 volts for the LED strips in the base.
Under the hood of the trade-fair exhibit
The Hygienic Seal Demonstrator can also be viewed from the inside. Via two hinges the rear panel can be folded up, making the interior freely accessible. In addition to the drive and electronics, there are also accessory components and a pressure-compensation tank that reliably compensates for volume changes of the water during temperature fluctuations.
The trade-fair model in individual parts
Before assembly, all individual parts of the exhibit were carefully laid out and counted, to detect missing components early.
Manufacturing the flanges from acrylic glass
All eight flanges of the exhibit were precisely CNC milled from transparent acrylic glass in several passes. Despite the simple geometry, the challenge was to achieve the appropriate surface finish for chamfers, grooves, visible surfaces and bonding surfaces.
Multiple cutter types were required for manufacturing. Single-edge, two-edge, taper cutters, countersinks and ball cutters were used to achieve the required contours and surface qualities. The circular groove for the centering bead of the seals was produced by trochoidal milling, in which the cutter moves slowly in small circular motions. This produced a slightly oval geometry that deliberately gives the EPDM seal room for elastic deformation.
Manufacture of the base and transport crate from wood
The base of the exhibit was precisely manufactured from wood on the CNC machine. The 15 mm multiplex panels are glued with flat dowels, ensuring a permanently stable connection. The surface is coated with a matte, deep-black two-component lacquer that looks high-quality while being durable and impact-resistant.
To ensure that the two halves of the transport crate fit precisely together, the second half was aligned exactly to the first during gluing.
Transport crate optimized for trade-fair use
For trade-fair use, a robust wooden crate made from 12 mm multiplex was produced, enabling secure transport and quick assembly of the exhibit. Two matching wooden shells are slid over the demonstrator from both sides and fixed with clasp fasteners. This allows the 65 kg exhibit to be lifted directly by ergonomic handles without first transferring it into a box.
Because each individual pipe segment is supported all around, the trade-fair model can be transported both standing and lying down. The fluid remains in the system, draining is not necessary for careful transport. For road transport it is recommended to place a foam pad between the pallet and the crate to further cushion shocks.
Real-time demo of the exhibit
The unedited 3-minute video shows the complete program sequence of the Hygienic Seal Demonstrator. From the agitation of the granulate through distribution and settling under UV light to clearing the mirror bottom with a view of the oil seal. The sequence matches exactly the presentation at the trade show booth.
Ooh, Aah, Wow! Customer magnets for your trade show booth.
Glaser engineering office develops and manufactures custom exhibition exhibits. As eyecatchers they attract visitors' attention at your trade show booth with a curious “Ooh”. The benefits of your product are made clear and tangible on the demonstration model with an astonished “Aah”. With a concluding “Wow!” you, your product and your brand stay in mind.
Technical details and notes for the trade show team
The following section describes the technical details of the exhibit and contains additional notes for the trade show team on handling.
Dimensions and weight
Exhibit: 390 x 390 x 977 mm
Base: 390 x 390 x 180 mm, Tube: Ø250 x 722 mm
Transport crate nominal size: 424 x 424 x 1000 mm
=> crate incl. handles and fittings: 504 x 434 x 1010 mm
Tare weight: 33 kg + fluid: 32 kg
=> exhibit: 65 kg
Exhibit: 65 kg + transport crate: 21 kg
=> transport weight: 86 kg
Stainless steel pushbutton with LED ring
Pressing the pushbutton starts the following sequence:
- 1s - Bright white flicker of all LEDs to attract attention.
- 5s - Reverse run, to loosen granulate (5s)
- 2s - Short strong forward run to distribute granulate
- 5s - Reverse run, to prevent vortexing
- 77s - Pause to allow the granulate to settle
- 50s - Several short reverse impulses to clear the mirror bottom, so that the oil seal becomes visible. (This step is skipped for the 2 min interval.)
- Restart by button press or by the timer control
(e.g. after 3 min)
If the button is pressed during a running sequence, bright red light draws focus to the deposited granulate.
Setting the interval
The sequence can be started manually by pressing the button or automatically by a configurable interval. To choose the duration, follow these steps:
- Press and hold the stainless steel button for 20s until the LED blinks rapidly
→ release - Choose the color or time for the interval
→ press the stainless steel button briefly - Press and hold the stainless steel button for 3s until the LED blinks
→ setting accepted
The following settings are possible in step 2:
Red → 2min*, Green → 3min, Blue → 5min, Magenta → 10min, White → 15min, Orange → 30min, UV → 60min, Off → Manual
*For the "2 min" interval, clearing the oil seal is skipped in the program sequence
Fluorescent acrylic granulate
The fluorescent PMMA granulate glows a strong orange under UV light and thus provides a high contrast to the complementary color of the slightly bluish glowing fluid. The cylindrical particles (grain size approx. 3 × 2 mm) are slightly denser than the fluid used, sink at about 1 cm/s and reach the bottom again after about 80 seconds. Due to their rounded shape, the grains roll off the protruding seal when agitated and then settle again.
Durable fluid
The fluid consists of the following components to be as durable as possible with minimal maintenance effort:
- 62.5% distilled water - provides optical clarity and, with low viscosity, good flow characteristics.
- 31.25% propylene glycol - lowers water activity for natural preservation, reduces evaporation and supports the lubrication of the shaft seal.
- 6.25% Alphacool Tec Protect 2 Clear - forms a thin protective film on brass and stainless steel, keeps the pH slightly alkaline and, together with antioxidants, counteracts optical aging under light.
- 0.5 ml SpaBalancer AntiFoam - acts as a silicone-based defoamer to prevent the formation of water bubbles on the pipe wall and the acrylic granulate and thus to prevent buoyancy.
Shaft feedthrough with oil seals
The shaft feedthrough was realized using two oil seals (4×12×0 BA – 72 NBR 902 – 4041107) from Freudenberg. Between the radial shaft seals the 4 mm stainless steel shaft is precisely guided by a full-ceramic ball bearing (4×12×4). The space between the two seals is completely filled with silicone grease to ensure reliable lubrication. The spring was removed from the upper oil seal and it was installed so that the static water pressure increases the radial contact pressure. A small 3D-printed sleeve made of blue PETG protects the oil seal from incoming granulate or contamination.
At the bottom of the container, behind the lowest acrylic glass flange, there is a reflective surface that reflects light entering from above. This additionally illuminates the floating granulate from below, which enhances its brightness.
Maintenance-free drive
The water screw is driven by a brushless, and thus maintenance-free, outer-rotor motor with up to 540 watts peak power at 12 volts. The motor is decoupled via elastic distance bolts, effectively reducing vibrations and structure-borne noise. An acrylic tube with a protective grille prevents any contact, while an additional propeller handles cooling. For maintenance on the oil seals, the entire drive unit can be easily removed.
Waterproof power supply
The energy supply for the exhibition piece is provided by a high-quality 12V switch-mode power supply from Mean Well. With IP65 protection, both the power supply and the potting of the supply cable are reliably protected against water. The on/off switch with integrated power LED is installed on the secondary side.
Volume and fluid
The acrylic cylinder has a capacity of 31.6 liters. With a temperature change of 20 kelvin the fluid expands by 0.66%, which corresponds to a volume of 205 milliliters. This expansion volume is absorbed by the expansion tank, which, with a capacity of 700 milliliters, provides sufficient reserve in both directions. The permanently atmosphere-vented tank was filled with 500 ml of fluid at 20 °C, so it can reliably compensate volume fluctuations. Since the hose connection at the bottom of the cylinder is the only opening, the water remains in the acrylic cylinder even with the drain valve open. As a result, the static pressure at the oil seal is almost zero, which is a significant advantage for the sealing of the oil seals.
Access and drain valve
The two water valves are intended exclusively for service and maintenance purposes and must not be operated during the exhibition piece's operation or transport. The access valve on the left connects the expansion tank to the water container. It is equipped with a safety clip and must remain permanently open to ensure continuous pressure equalization. On the right is the drain valve, which is connected to a drain hose. Its end is secured with a plug and held in place by a clip.
Bleed screw
The bleed screw is intended exclusively for service and maintenance work. There is a bore in the upper full flange of the exhibition piece that reaches into the interior of the water container. This access can be opened via a set screw to release remaining air bubbles. It should be noted that the entire system must be set to slight overpressure via the drain hose.
Fusing of the LED module
The power supply of the LED module above the cylinder is routed via three threaded rods. The front left rod serves as ground (GND), the front right as the DMX data line and the rear for transmitting the 24 V DC supplied by the DC/DC converter. All conductors are circuit-protected against conductor contact and short circuit, ensuring safe operation. Additionally, an integrated circuit breaker secures the power supply. In case of a trip it can be easily reset by pressing the red button.
Threaded flange for fastening
To securely fix the exhibition piece on a table, an M10 internal thread is provided in the center of the base plate. The demonstrator can be fastened to the table from below using a screw through this thread. For some positioning tolerance, a 20 mm diameter hole in the table is recommended. A suitable screw with washer and handwheel is designed for table thicknesses from 20 to 45 mm and is stored in the base of the exhibit. It is important that the maximum insertion depth of 35 mm is not exceeded to avoid a collision with the centrally located drive unit.
Cable routing with strain relief
The cable routing of the exhibition piece is designed to run invisibly under the base. A minimum 42 mm diameter hole in the tabletop is required for routing the Schuko plug. Behind the base flap there is a groove through which the supply cable can be pulled out to the required length. Using a 3D-printed rotary disc the cable can be fixed, so the appropriate length is always available.
Water-protected supply cable
The 3 meter 230 V supply cable is connected directly to the waterproof IP65 power supply, without an intermediate coupling to provide maximum protection against moisture. For transport the supply cable is stowed in the base of the exhibition piece.
Accessories in the transport case
The transport case of the exhibit contains an electrically powered air duster, with which dust on the acrylic flanges between the screws can be quickly and easily removed. The box also contains a small tool box as well as various accessories that facilitate assembly.
Small toolbox
As compact as the toolbox is, the maintenance effort is equally low. The water remains in the exhibition piece permanently and is durable for years. For assembly and possible emergencies the following items are still included:
- 18 mm socket and ring spanner made of plastic to protect the stainless steel screws
- USB wall charger with USB-C cable for charging the electric air duster
- Microfiber cloths for cleaning the transparent acrylic segments
- Hex keys for the bleed screw and for retightening the set screw of the shaft coupling
- Test strips for checking the pH value
Torques for the bolted connections
The screws and nuts of the flanges were tightened alternately and in a cross pattern with the following tightening torques.
- Lid: 3.6 Nm
- Top: 3.6 Nm
- Bottom: 3.8 Nm
- Base: 4.5 Nm
Flip-top lid with hinged lift hinges
Via two internal surface-mounted hinges, the lid of the base rear panel can be swung up 170°. This makes the interior with technology and accessories of the trade-fair exhibit comfortably accessible. For any repair and maintenance work, the entire base plate of the pedestal can also be removed.
CNC-engraved nameplate
The permanently mounted nameplate defines the intended use of the trade-fair exhibit and contains the relevant information on year of manufacture, project and operator. It clearly indicates that this is a demonstration unit for use at trade fairs and exhibitions and specifies the conditions for proper operation. The URL given below points to this project page.
All technical data on the trade-fair exhibit
On the base of the trade-fair exhibit a notice plate is attached to the inside of the flap on the rear, providing the trade-fair team with all important technical information at a glance. It contains details on interval control, volumes, fluid composition, dimensions and weights as well as valves, transport and cleaning.
The trade-fair exhibit in Augmented Reality (AR)
The Hygienic Seal Demonstrator can be experienced not only live at the trade fair but also virtually in augmented reality. With a smartphone the model can be placed without an additional app in the room and viewed from all perspectives.
Virtual trade-fair exhibit
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Scan the QR code with the camera app
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Open the displayed link
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Select the cube icon at the top right
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Point the camera at the floor
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Tap to place
More 3D models and renderings
The following are renderings of the trade-fair exhibit in large format. They were rendered over several hours, to reproduce reflections, shadows and light refractions particularly realistically.
THANK YOU!
A big thank you to the Hygienic-Seal team from Freudenberg in Weinheim for the trusting and appreciative collaboration. The close exchange and the cooperative partnership made this project a real success in a short time. Thanks for the refreshing meetings, the always friendly contact and the warm visits.
